Skip to Content

First Look: Equivalence for iPhone

by Cory Bohon Sep 22nd 2008 at 1:00PM

Keeping with the famous science teacher saying of "every number must have a unit," Equivalence (iTunes link) is the one-stop converter for all things units. Did we say "one-stop?" Why yes we did, because Equivalence can convert between over 260 units in 31 categories.

Once of the nice features of Equivalence is the ability for the application to auto update the unit conversions over the air, instead of through the App Store. So, if the developer decides to add a unit, or if a unit were to change, updates could get pushed out to the application.

The beauty of this application is when you flip your iPhone into landscape mode. Just like the built-in iPhone calculator, this application adds much more functionality when horizontal, including a calculator that can add units together.

Bottom line: This is the best unit converter for the iPhone, hands-down. Be sure to take a look at our gallery of Equivalence screenshots. You can buy Equivalence from the iTunes App Store for $4.99 (US).

Update: The developer has dropped us an email to let us know about a special promotion. Equivalence will sell on the App Store for $1.99 until October 6th. The pricing changes have already been submitted to Apple for approval and should appear soon. Also, we have added two new screenshots in the gallery showing off the landscape mode in Equivalence.



First Looks: Equivalence for iPhone



View Tags

Related Stories

Categories

iPhone App Store iPod touch

Keeping with the famous science teacher saying of "every number must have a unit," Equivalence (iTunes link) is the one-stop converter for...
 

Add a Comment

Sign in »
*0 / 3000 Character Maximum

26 Comments

Filter by:
iomatic

Actually you could calculate cascading ems based on a defined unit. I'd like "reverse" em though-- that is, what is the point size value of x em based on the predefined point size, (e.g., the baseline em is 11px, which is 1.0 em; what is 1.2 em in pixels?)

http://riddle.pl/emcalc/

THANKS!

September 30 2008 at 7:43 PM Report abuse rate up rate down Reply
Eric Smith

If every number must have a unit, what's the appropriate unit for the fine structure constant?

September 23 2008 at 6:16 PM Report abuse rate up rate down Reply
SMario

Very nice tool!

Have you some localized versions (german) planned?

September 23 2008 at 7:20 AM Report abuse rate up rate down Reply
Itai Ferber

Well, the update has gone live, and I've come to the conclusion that Equivalence is an awesome app at an awesome price... :)

September 22 2008 at 9:02 PM Report abuse rate up rate down Reply
Wry Cooter

Perhaps Corey should boldface the phrase "can convert between over 260 units in 31 categories."

Because most of us that would even be interested in this, got "Units" for free the first week of the appstore, and are getting by pretty well in its 14 categories of unit conversion without hitting a wall yet.

If Units were part of Apples built in Calculator app, as is a similar code base on the desktop, in the menubar when Calculator is up, would Gruber cry "Apple is unfair to developers?"

September 22 2008 at 8:22 PM Report abuse rate up rate down Reply
Itai Ferber

The discount sounds is yet another reason why I need to buy this, and now. I'm a chemistry student, so this unit conversion stuff is really useful. Plus, I'll be taking physics next year, making the purchase even sweeter.

However, iTunes won't let me buy it yet, which is annoying. I guess I'll just refresh the page every 30 seconds until the price change hits... :P

September 22 2008 at 5:47 PM Report abuse rate up rate down Reply
Sway

Coversions for EM and EN are missing, no sale

September 22 2008 at 4:34 PM Report abuse rate up rate down Reply
1 reply to Sway's comment
Bryan Henry

En and em have no concrete physical definition as they are dependent on the point size of the font being considered, so including them in the app would not make much sense. If you have more requests for units, though, feel free to send an email my way - I field quite a few requests each week and units can be added with a database update easily.

Bryan Henry, ApogeeDev
dev@apogee-dev.com

September 22 2008 at 6:26 PM Report abuse rate up rate down Reply
Bryan Henry

You can find some landscape screenshots at
http://apogee-dev.com/equivalence/screenshots.

Bryan Henry, ApogeeDev
dev@apogee-dev.com

September 22 2008 at 3:33 PM Report abuse rate up rate down Reply
tevetorbes

The program looks neat, but you can do this for free without downloading anything by going to google.

It knows just about every unit conversion you can think of.

September 22 2008 at 3:16 PM Report abuse rate up rate down Reply
Zommah

Units by Crossroad is definitely superior to this and every bit as powerful (also only 99cents).

So the 'hands-down' comment is baffling if you haven't tried it.

September 22 2008 at 3:15 PM Report abuse rate up rate down Reply
1 reply to Zommah's comment
Bryan Henry

Units is definitely good in its own respect, and its developer did a good job with it. It lacks Equivalence's power, however, because it as well as any similar app in the AppStore lacks this app's landscape mode. The landscape mode allows completely free-form calculations with units which is why I believe Cory says its "the best...hands-down."

Bryan Henry, ApogeeDev
dev@apogee-dev.com

September 22 2008 at 3:39 PM Report abuse rate up rate down Reply
Buy an ad here

Hot Apps on TUAW

Tweets

© 2012 AOL Inc. All Rights Reserved.